Pulse width modulated (PWM) power conversion circuits or converters can be used for DC-DC conversion to process power by modulating the amplitude of the current in an inductor. A variety of different DC-DC converter topologies have been developed to convert an input signal, such as a DC input voltage or current, to provide a DC output voltage or current signal to drive a load. DC-DC converters may operate in different modes with respect to the conduction of the inductor current, including continuous conduction mode (CCM) where the inductor current does not reach zero, discontinuous conduction mode (DCM) where the inductor current is zero for some time interval, and transition mode or critical conduction mode (TM or CrCM) at the boundary between CCM and DCM, in which the inductor current is zero for a near zero time interval. In certain applications it is desirable to allow a DC-DC converter to operate in more than one mode, for example, to accommodate variations in load conditions. However, dedicated control circuitry for operation in each mode and logic circuitry to switch between modes reduces converter efficiency and power density.